\documentclass[../article_algorithms.tex]{subfiles}
\begin{document} 
\begin{tcolorbox}[width=(\linewidth-2cm)]
\begin{algorithm}[H]
\DontPrintSemicolon
\footnotesize
\SetAlgoLined
$C = \text{SPR-ADMM-LINEAR}(Y)$\;
\KwIn{Data Set: $Y \in \RR^{M \times S}$} 
Terminate $\leftarrow$ False, $k \leftarrow 0$\;
Initialize $A^0, C^0, \Delta^0$ to 0\;
\Repeat{Terminate}{
\begin{enumerate}
\item Update $A^{k+1}$ as solution of the equation
    \begin{equation*}
    \lambda(Y^T Y + \rho I) A^{k+1} = \lambda Y^T Y + \rho C^k - \Delta^k.
    \end{equation*}
\item Update $C^{k+1}$ as $C^{k+1} = J - \Diag(J)$ where
where $J = S_{\frac{1}{\rho}}(A^{k+1} + \Delta^k / \rho)$.
\item Update $\Delta^{k+1} = \Delta^k + \rho (A^{k+1} - C^{k+1})$.\;
\item $k \leftarrow k+1$\;
\item Terminate $\leftarrow \|A^k  - C^k\|_{\infty,\infty} \leq \epsilon$\;
$\quad$ and $\|A^k  - A^{k-1}\|_{\infty,\infty} \leq \epsilon$ \;
$\quad$ or $k \geq$ max\_iterations.
\end{enumerate}
}
\end{algorithm}
\end{tcolorbox}
\end{document}
